Stephen King’s new 842-page epic, “11/22/63,” defies neat categorization. It’s at once a high concept thriller, a science fiction saga and an intricately researched work of historical fiction that retraces Lee Harvey Oswald’s steps in the months and weeks leading up to the Kennedy assassination.

“11/22/63” opens in contemporary Maine, as high school English teacher Jake Epping is sent on a bizarre errand for his dying friend Al, who owns a diner with a mysterious time portal to 1958. Al wants Jake to go back in time to stop Oswald from shooting JFK. The rest of the novel unfolds in the late 1950s and early 1960s, an era that Mr. King captures with minute details such as the price of gas (19.9 cents a gallon) and a dinner of meatloaf and apple pie (95 cents). Mr. King also managed to squeeze in a stopover in Derry, Maine, the fictional town where children are killed by an evil, shape shifting spirit in his 1986 novel “IT.”

Jake’s mission leads him to Dallas, where he tracks Oswald and a cast of real historical figures such as the Russian petroleum geologist George de Mohrenschildt, a friend of Oswald’s, and Ruth Paine, who took in Oswald’s wife, Marina, when the pair separated. Mr. King spent a week in Dallas, visiting Oswald’s apartment and the site of the shooting, and spent months researching the assassination.

“It’s the first time I’ve ever worked with him that his imagination was tethered to history,” says Scribner Editor-In-Chief Nan Graham, who has edited Mr. King for 17 years and also edited “Libra,” Don DeLillo’s novel about Lee Harvey Oswald. “It doesn’t get to go off the way he does.”

Mr. King says he’s wanted to write about the Kennedy assassination since 1973, when he was just beginning his career as a novelist. He vividly remembers where he was the moment he learned of Kennedy’s death. “I was in a converted hearse,” he says. He offers a quick explanation for the macabre setting: his town didn’t have a high school, so his mother and some other parents hired a taxi driver to ferry a group of students to a nearby town’s high school in the hearse. (Another grim detail: one of the students riding with him that day was the girl who inspired his chilling 1974 novel “Carrie.”). The driver had the radio on, and that’s when he heard the news.

You’ve never written historical fiction before. What took you in this direction?

I like doing different things because they keep what I do fresh and you get out of the rut a little bit. There’s a real challenge — I started to say there’s a real danger, but there’s no danger sitting in a room, the only danger is when the critics start to sharpen their little claws — there is a real challenge in trying to keep the story in front of the history. It’s exciting to take a real person like Lee Harvey Oswald and say, I want to give him some dimension, put some flesh on his bones, and I want him to be a real character.

Are you hoping this novel will attract new readers, maybe historical fiction fans?

I do hope for it….I always thought this might be a book where we really have a chance to get an audience who’s not my ordinary audience. Because you’d always like to say to people, ‘Well, if you try this you might like it.’ They’re a little bit like children with their vegetables. I ran into a lady in the supermarket in Florida. Old lady. There’re lot of old people in Florida; it’s like the law. I was coming up the house wares aisle and she said, “I know who you are, you’re that writer, you write those horror stories,” and I said, “Yes, ma’am, I guess,” and she said, “I don’t read that kind of thing. I respect what you do but I don’t read those. I like uplifting things like that ‘Shawshank Redemption.’” I said, “I wrote that one, too,” and she goes, “No, you didn’t,” and she just went on her way.

You first had the idea for “11/22/63” in the early ‘70s, and your last big novel, “Under the Dome,” was also an extension of an idea that you’d had decades before. Why are you tackling these ambitious, decades old projects now? Do you feel some pressure to publish them when you’re in your creative prime?

That’s what it is, sure, yeah. Tie up the loose ends. That’s not to say that I have any premonition that I’m going to die or anything like that. These things have been there for a long time. Now’s the time to do them if I’m going to do them at all. I’m not getting any younger…I might have ten productive years left or I might not.

And you never let go of the idea for “11/22/63”?

It was always a good idea. I don’t keep a writers notebook because the good ideas stick, and this one stuck for 35 years before I got around to it.

Do you have other partially written novels?

Yeah, I do, but not anything that I would probably go back to.

How many unfinished manuscripts do you have?

Probably a dozen.

You’ve largely avoided time travel in your novels and have said it presents too many narrative and logical pitfalls. How did you tackle it?

My solution to it was to make it totally unscientific. It’s a device. Time travel is just a device to say, I’m going to take someone from the present and put them in the past. And it’s a perfectly acceptable literary device. In “Gulliver’s Travels,” Jonathan Swift never says, there was a genetic mutation that turned them into little tiny people. They’re just tiny people. It’s the same thing. And there are all sorts of paradoxes inherent in time travel. There’s a point in the book where Jake says to Al Templeton, “What if you went back and killed your grandfather?” And Al says, “Why the f— would I want to do that?”

You won a National Book Award for distinguished contribution to American letters, have been published in the New Yorker and have a story in the current issue of literary magazine Granta. Do you feel like your reputation as a horror writer has shifted in recent years and that critics are defining your work more broadly?

People have come around to the idea that you can talk about a lot about serious subjects without ever leaving the horror genre. This is not just my deal. There are writers like Ruth Rendell that are taken quite seriously. There are a lot of other popular writers who’ve gotten some real cred. Not everybody takes me seriously. God knows I want to tell stories that people like. I don’t think I’m ever going to convince [literary critic] Harold Bloom that I’m worth a s—.

How do you think writing a historical novel and getting some prestigious awards will shape your legacy?

Yeah, I mean, I’ve never really concerned myself with a legacy. I’ve never fooled myself that I’m going to have much of popularity beyond my life time. There may be one or two books that people read later on, some of the horror stories like “Salem’s Lot” and probably “The Stand.”

About Speakeasy

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